Fluid discharge device with deformable lance

ABSTRACT

AN IMPROVED ACTIVATOR MECHANISM FOR A RESERVE ELECTROCHEMICAL BATTERY. THE BATTERY IS COMPRISED OF AN ACTIVATOR SECTION AND A BATTERY COMPARTMENT SEPARATED FROM THE ACTIVATOR SECTION BY A PIERCEABLE MEMBRANE. TO ACTIVATE THE BATTERY, THE MEMBRANE, SEPARATING THE TWO COMPARTMENTS, IS PIERCED BY A LANCE, ALLOWING A LIQUID TO FLOW FROM THE ACTIVATOR SECTION INTO THE BATTERY COMPARTMENT. THE LANCE IS CONSTRUCTED OF DEFORMABLE MATERIALS SO THAT UPON PIERCING THE DIAPHRAGM, THE LANCE IS BENT AND IS PREVENTED FROM FURTHER PENETRATION INTO THE BATTERY COMPARTMENT.

July 3, 1973 w, c. MERZ ETAL 3,743,545

FLUID DISCHARGE DEVICE WITH DEFORMABLE LANCE Filed July 16, 1970 FIG. I

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INVENTORS WILLIAM C. MERZ GEORGE J. METHLIE ROLF W. SATTLER OLEG S.SAVINOV BY M AT TORNE Y United States Patent f") 3,743,545 FLUIDDISCHARGE DEVICE WITH DEFORMABLE LANCE William C. Merz, Aldan, George J.Methlie, Centre Square, Rolf W. Sattler, Norristown, and Oleg S.

Savinov, North Wales, Pa., assignors to Honeywell Inc., Minneapolis,Minn.

Filed July 16, 1970, Ser. 55,518 Int. Cl. H01m 21/10 US. Cl. 136-114 4Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION Field ofthe invention A deferred-action type of primary battery wherein prior toactivation the action of the battery is prevented by a pierceablediaphragm separating the battery cells from the electrolyte or theelectrolyte solvent.

Description of the prior art A substantial number of prior art patentsshow deferred-action type batteries, wherein activation is achieved bybreaking a seal which separates the electrolyte from the electrodes.Representative of prior art are Pats. 3,239,385 and 3,298,868. Each ofthe above patents shows a lance-type initiating mechanism for a reservebattery. The lance is mounted within a collapsible cup, which prior toactivation is filled with a liquid. The lance is mounted in such a waythat, upon compression of the cup, it is forced through the diaphragmwhich is located in a position to close a passage between the cup andthe battery compartment. To activate the battery, the diaphragm ispierced by the lance and upon further compression of the cup the lanceis forced into a central column in the battery compartment. To preventthe lance from completely blocking the passage, the lance is providedwith spiral grooves in the nature of a drill. Nonetheless, since thelance remains in the port between the liquid reservoir and the cellstack it restricts or impedes the liquid flow to the cells. This resultsin a time delay in the activation of the battery. Another disadvantageof such prior art arrangement is that the lance remains in the batterysection after the activation. The presence of the lance in the batterycompartment provides a conductive path which results in increasedintercell leakage.

SUMMARY OF THE INVENTION The invention described herein will find useprimarily in the type of systems where a liquid is separated from otherelements until application of an outside signal. In particular, thepresent invention will find use in a reserve activated battery in whichthe liquid is separated from the battery cells until it becomesdesirable to activate the battery. The term battery as used in thisspecifica tion may mean either a single current-producing cell or aplurality of current-producing cells arranged in series or in parallel,as the requirements of a particular situation may dictate. Separatecompartments are provided for the electrolyte and the battery cells. Theelectrolyte compartment may be simply a portion of the battery casewhich is separated from the rest of the case by a pierceable diaphragm.To activate the battery, the diaphragm is pierced by means of a lance,which is forced through the diaphragm upon application of a signal.

In the preferred embodiment of the present invention, a compressible cupis mounted within the electrolyte compartment. The cup is mounted withthe open end facing the aperture closed by the pierceable diaphragm. Thelance for piercing the diaphragm is mounted within the cup so that uponcompression of the cup the lance is forced through the diaphragm. Thelance is equipped with a cross-member at a point near its tip. Thelength of the cross-member exceeds the diameter of the apertureconnecting the battery compartment and the activator compartment, andthereby prevents the penetration of the lance into the batterycompartment beyond that point. The lance is sutficiently rigid to piercethe membrane before bending, and sufiiciently deformable to bend afterthe cross-member prevents further forward movement of the lance.

Several advantages are offered by the use of the present invention.Since the lance is prevented from penetrating into the batterycompartment, the obstruction caused by it to the flow of electrolytefrom the storage compartment into the battery cells is considerablyreduced or even eliminated. Additionally, intercell leakage issubstantially reduced by keeping the lance out of the batterycompartment.

An object of the present invention is, therefore, to provide an improvedactivation mechanism for deferredaction batteries.

A further object of the present invention is to provide a means forrapid activation of such batteries, thus making it possible to maintainthe battery in non-activated state until just prior to use.

These and other objects will become apparent to those skilled in the artof batteries upon examination of the following specification, claims,and the drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a vertical cross section of adeferred-action battery according to the present invention;

FIG. 2 illustrates a preferred embodiment of a lance for use in theembodiment of FIG. 1;

FIG. 3 is a fragmentary section of a view similar to FIG. 1 during adifferent stage of operation, when the battery is in process ofactivation; and

FIG. 4 is a fragmentary section similar to FIG. 1, representing thebattery after full activation.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1 of thedrawing, a reserve activated battery is shown having a housing with anexternal cylindrical shell 10. Shell 10 is constructed of material whichis sufficiently strong to withstand the pressures generated inside thebattery. A cover member 11 closes the upper end of the cylindrical shell10. The bottom end of the shell is closed by a terminal plate 12 whichcarries the battery terminals and provide means for electricalconnection from inside to the outside of the battery housing. A bulkhead14 separates the cylindrical housing into two compartments, a batterycompartment 15 and a liquid storage compartment 16. Bulkhead 14 has acentral aperture 17, providing a passage between liquid storagecompartment 16 and battery compartment 15. A diaphragm 18 is positionedwithin aperture 17 to close the passage until activation of the batteryis desired. Diaphragm 18 is constructed of material such that it can beruptured by piercing.

A compressible reservoir cup 20 is mounted within the liquid storagecompartment 16. The cup is mounted with its open end against bulkhead14, such that upon compression of cup 20, the only path open to theliquid flow is through passage 17 into battery compartment 15.

Mounted within reservoir cup 20, at a location opposite opening 17 anddiaphragm 18, is a lance 21. Lance 21 has a pointed lower end facingdiaphragm 18. The feature of the lance in the present invention is thatit is collapsible. It is constructed of three pieces of stainless steelwire 22, 23 and 24, welded together and forming the pointed end of thelance. At the other end, the three wires are welded to a disc 25 atthree separate locations, providing a stable tripod configuration. Atthe pointed end of the lance and slightly above it, a cross-member 26,as more clearly visible from the illustration of FIG. 2, is welded.Cross member 26 is longer than the cross-section of opening 17 inbulkhead 14. The purpose of the cross-member is to prevent thepenetration of the lance further into the battery compartment 15.

At the center of cover member 11 is located a gas generating assemblycomprised of a chemical propellant or gas generator 30 held by a gasgenerator cup 31 threaded into cover member 11. A pair of lead wires 32are brought into contact with chemical propellant 30 through a plasticplug 33.

Battery compartment contains a plurality of battery cells shown at 40.The cells are arranged around a central column which is coaxial with thecylindrical shell 10 and which extends the entire height of batterycompartment 15. The central column has a bore extending the entirelength of battery compartment 15, from passage 17 in bulkhead 14 toterminal plate 12. A plurality of apertures 41 are provided from thecentral column into the individual cells of the battery. The liquid isthus allowed to flow from compartment 16 into cells 40 by means of thebore in the central column and apertures 41.

Terminal plate 12 carries positive and negative terminals 43 and 44.Cells 40 are arranged in a series configuration, forming a cell stack.Terminal 43 is connected by means of a conductor to the upper end of thecell stack, while terminal 44 is connected to the lower end of the cellstack.

Reservoir cup is shown in the preferred embodiment as constructed in aform of a bellows. in this configuration, the cup can be easilycompressed by application of force to the exterior of the cup. Thereservoir cup could also take other forms, such as for example thedeformable activator cup of the type shown in patent 3,239,385.

OPERATION The operation of the invention can be most readily understoodby referring to FIGS. 1, 3 and 4, illustrating the battery in differentstages of activation. When activation is desired, a potential is appliedto lead Wires 32 of the gas generating assembly. The gasgeneratingassembly can take many different forms. In this preferred embodimentthere is utilized a moderate rate chemical propellant 30 activatable byan application of electric potential by means of a suitable source ofelectrical energy, not shown in the drawing, but connected to by meansof lead Wires 32. Upon application of electrical potential to chemicalpropellant 30, the propellant ignites and thereafter burns at apredetermined rate to generate a gas. The generation of the gas resultsin an increase in pressure within compartment 16, external to reservoircup 20. Sufficient pressure is generated to com-press cup 20 and forcethe sharp end of lance 21 downwardly through diaphragm 1'8. Diaphragm 18is pierced by the sharp point of lance 21 and is then further rupturedby the increase in pressure within the fluid and by the flow of theliquid rushing through opening 17 into battery com 4 partment 15. Thisis best shown by reference to FIGS. 3 and 4.

As cup 20 is further compressed by the expanding gas within compartment16, lance 21 is forced further in the downward direction. However, dueto cross-member 26, which prevents further penetration of the lance intothe battery compartment, the further compression of cup 20 causescomponent wires of the lance to bend. The initial configuration of lance21 is rigid enough to puncture the diaphragm, but as further movementbrings the cross member to rest against the heavier walls of bulkhead14, the Wire members 22, 23 and 24 of lance 21 buckle. As cup 20compresses further, lance 21 collapses completely in the manner shown inFIG. 4. The collapsing of lance 21 substantially removes the lance frominterferring with the liquid flow into the battery compartment. Further,by preventing the penetration of the lance into the battery compartment,a potential intercell leakage path is eliminated.

While in the preferred embodiment the cup is shown as compressed by agas generator type of activation force, other means such as fluid ormechanical, could clearly be used to achieve the purpose. Changes can beeffected in detail of construction without departing from the spirit andscope of the invention as defined in and limited solely by the appendedclaims.

We claim:

1. In a deferred-action electrochemical battery having an activatorsection and a battery compartment separated from said activator sectionby a bulkhead with an aperture closed by a pierceable diaphragm, saidactivator section comprising:

a compressible activator cup for containing liquid electrolyte mountedin said activator section, said cup having its open end sealed againstsaid bulkhead and enclosing said diaphragm; and

a deformable lance having a first end mounted within said cup at aposition opposite its open end and having a pointed second end directedtoward said diaphragm in said bulkhead;

said lance further having an expanded portion at and slightly above thepointed end thereof, a cross sectional dimension of said expandedportion exceeding the diameter of said aperture closed by saiddiaphragm;

whereby upon application of external force on said cup, said cup iscompressed and said lance is forced to pierce said diaphragm and uponapplication of further force, said cup is further compressed, forcingthe liquid electrolyte into said battery compartment, said expandedportion preventing said lance from penetrating further into said batterycompartment.

2. Apparatus according to claim 1, wherein said activator cup isconstructed in the form of a bellows.

3. Apparatus according to claim 1, wherein said deformable lance iscomprised of three wires joined at one end to form a pointed end andmounted individually at the other end at separated points to therebyform a stable tripod arrangement.

4. Apparatus according to claim 1, wherein said deformable lance iscomprised of a plurality of elongated members, joined at one end to forma pointed end and mounted individually at the other end to form a stablearrangement.

References Cited UNITED STATES PATENTS 1/1967 Smith et al. 136-114 2/1966 A-miet et a1. 1'36-62 US. Cl. X.R. 13 6-90

